For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningOnStar Overview
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect
to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic
Services.
The OnStar system status light is next to the OnStar buttons. If the status light
is:
• Solid Green: System is ready ...
Vehicle Messages
Messages displayed on the DIC indicate the status of the vehicle or some action
that may be needed to correct a condition. Multiple messages may display one after
the other.
The messages that do not require immediate action can be acknowledged and cleared
by pressing SET/CLR. The messages tha ...
Taillamps, Turn Signal, Sidemarker, Stoplamps, and Back-Up Lamps
Trunk Deck Inboard Taillamps
1. Open the trunk.
2. Remove the trunk deck trim cover (1).
3. Remove the bulb socket (2) by turning counterclockwise and pulling straight out.
4. Remove the bulb from the socket.
5. Install the new bulb in the bulb socket.
6. Install the bulb socket by turni ...